public class kehou3_1 {
	public static void main(String args[]) {
		int sum = 0;
		int n = 10;
		for(int i = 1;i<=n;i++) {
			sum = sum+fact(i);
		}
		System.out.println(sum);
	}
       public static int fact(int i) {
		if(i == 0)
			return 1;
		else
			return i*fact(i-1);
	}
}
